Clinical Effects of High Risk Neuroblastoma with Chromosome 1P36 Deletion Post Autologous Stem Cell Transplant

Objective By describing the clinical features of post autologous hematopoietic stem cell transplantation high risk Neuroblastoma (HR-NB) patients with 1 p36 deletion and their clinical outcomes,the goal was to make further progress in better survival rate and life quality.Methods A retrospective study of all HR-NB patients with lp36 deletion,who attended the pediatric hematology oncology centre from April 2014 to April 2016 and received systematic treatment and follow-up care,were performed.Clinical stage,risk group classification,treatment and assessment were according to NB-2007-protocol of the centre.The end of follow-up was Dec 31st,2016.Results A total of 11 HR-NB patients with 1 p36 deletion,all INSS-Ⅳ,were included in the study (4 male and 7 female).The average age was 43 months.Primary tumor sites of 3 cases were in the posterior mediastinum,and the test 8 cases were in retroperitoneal or adrenal gland.There were 11 cases with bone marrow metastasis and 10 cases with multiple bone metastasis.There were 6 cases with distant lymph node metastasis,5 cases with visceral metastasis,such as in liver.N-myc gene amplification was detected in 4 patients.All the patients were treated with 4-5 courses of chemotherapy before the operation.The amount of infused stem cells was (2.62-10.68) × 106/kg,and the median follow-up time was 14.9 (9-32) months.4 patients relapsed or progressed,1 of whom relapsed after 3 months of stopping retinoic acid and died after giving up treatment.3 cases occurred tumor progression in 3,5 and 6 months after the infusion respectively.2 patients died after abandonment,and 1 patient was still under treatment.All the 7 patients in have stable disease.Conclusions HR-NB patients with 1 p36 deletion had a high risk of developing bone marrow and bone metastases,and 1/3 of them were associated with N-myc gene amplification.However,in 3-6 months after reinfusion and during retinoic acid maintenance therapy,tumor progression may happen and lead to poor prognosis,suggesting the strength of systemic treatment of these patients is not quite enough.